The correct answer for the question that is being presented above is this one: "A. The accepted model of the atom was changed.<span>" </span>J J Thomson discovered the electrons and performed experiment using the cathode ray tube
Here are the following choices:
<span>A. The accepted model of the atom was changed.
B. The accepted model of the atom was supported.
C. Cathode ray tubes were no longer used in experiments due to poor results.
D. Cathode ray tubes became the only instrument of use in the study of atoms</span>
To balance this equation, first we should consider balancing C because it only presents in one reactant and one product. Assuming the coefficient of C6H6 is 1, there are 6 C's in the reactant, so it generates 6CO2. Then consider balancing H for the same reason. If the coefficient of C6H6 is 1, there are 6 H's in the reactant, so it generates 3H2O.
Now that the coefficient of the products are determined, we can balance O. There are 6*2=12 O's in CO2 and 3*1=3 O's in H2O. So the total number of O in the products is 12+3 = 15. O2 is the only reactant that contains O, so to balance the equation, the coefficient of O2 should be 15/2.
Now the equation looks like:
C6H6 + 15/2O2 ⇒ 6CO2 + 3H2O.
Times both sides of the equation by 2 results the final answer:
2C6H6 + 15O2 ⇒ 12CO2 + 6H2O
Answer= C) CN contains a covalent bond.
Here's the equation you use: Density = mass/volume
1) 5.2g/cm^3 = m/3.7cm^3
2) m = 5.2g/cm^3 x 3.7cm^3
3) m = 19.24g
You can check the answer by plugging it in
19.24g/3.7cm^3
= 5.2g/cm^3